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Transfer of technology is a complex process with many facets, options and constraints. While the concept is an important step in bringing industrialization process to agricultural based countries, it is clear, however, that a country will only benefit from a new technology if it addresses a real need, and if it can be absorbed and adapted to suit the existing cultural and technological base.

International Atomic Energy Agency, as UN body, has a mandate to promote nuclear applicationsand assist Member States in transfer of technology for peaceful applications. This mandate has been pursued by many different mechanisms developed in the past years: technical assistance, coordinated research programmes, scientific and technical meetings, publications, etc. In all these activities the Agency is the organizer and initiator, but main contributions come from expert services from developed countries and, increasingly, from developing countries themselves. The technical cooperation among developing coutries more and more becomes part of different programmes.

In particular, regional cooperation has been demonstrated as an effective instrument for transfer of technology from developed and among developing countries.

Some examples of actual programmes are given.  相似文献   

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The aim of this research was to establish the constituents of Bauhinia pulla as anti-diabetic agents. A phytochemistry analysis was conducted by chromatographic and spectroscopic techniques. The alpha-glucosidase inhibitory assay screening resulted in the isolation of eight known compounds of quercetin, quercitrin, luteolin, 5-deoxyluteolin, 4-methyl ether isoliquiritigenin, 3,2′,4′-trihydroxy-4-methoxychalcone, stigmasterol and β-sitosterol. Ethanol leaf extracts showed potential effects, which led to a strong inhibitory activity of isolated quercetin at 138.95 µg/mL and 5.41 µg/mL of IC50, respectively. The docking confirmed that flavonoids and chalcones had the same potential binding sites and responsibilities for their activity. This study was the first report of Bauhinia pulla chemical constituents and its alpha-glucosidase inhibition.  相似文献   
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MRI techniques have been developed that can noninvasively probe the apparent diffusion coefficient (ADC) of water via diffusion-weighted MRI (DW-MRI). These methods have found much application in cancer where it is often found that the ADC within tumors is inversely correlated with tumor cell density, so that an increase in ADC in response to therapy can be interpreted as an imaging biomarker of positive treatment response. Dynamic contrast enhanced MRI (DCE-MRI) methods have also been developed and can noninvasively report on the extravascular extracellular volume fraction of tissues (denoted by ve). By conventional reasoning, the ADC should therefore also be directly proportional to ve. Here we report measurements of both ADC and ve obtained from breast cancer patients at both 1.5 and 3.0 T. The 1.5-T data were acquired as part of normal standard of care, while the 3.0-T data were obtained from a dedicated research protocol. We found no statistically significant correlation between ADC and ve for the 1.5- or 3.0-T patient sets on either a voxel-by-voxel or a region-of-interest (ROI) basis. These data, combined with similar results from other disease sites in the literature, may indicate that the conventional interpretation of either ADC, ve or their relationship is not sufficient to explain experimental findings.  相似文献   
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Mathew  M.  Wisner  B.  Ridwan  S.  McCarthy  M.  Bartoli  I.  Kontsos  A. 《Experimental Mechanics》2020,60(8):1103-1117
Background

Digital Image Correlation (DIC) is a length scale independent surface pattern matching and tracking algorithm capable of providing full field deformation measurements. The confident registration of this pattern within the imaging system becomes key to the derived results. Practically, conventional speckling methods use non-reliable, non-repeatable patterning methodologies including spray paints and air brushing leading to increased systematic and random errors based on the user’s experience.

Objective

A methodology to develop a speckle pattern tailored to the imaging and experimental conditions of the given system is developed in this paper.

Methods

In this context, a novel bio-inspired speckle pattern development technique is introduced, leveraging spatial imaging parameters in addition to frequency characteristics of speckle patterns, enhancing the results obtained through DIC. This novel technique leverages gradient parameters in the frequency spectrum obtained from patterns fabricated using a bio-templating manufacturing technique.

Results

The analysis presented shows that optimized gradient features alongside tailored spatial characteristics reduce errors while increasing the usefulness of DIC results across the entire region of interest. With this new approach, gradient information is derived from the bio-templated pattern, extracted, optimized and then convolved with spatial properties of a numerically generated 2D point clouds which can then be transferred onto actual specimens. Numerical error analysis shows that the optimized patterns result in significant reduction in root mean square error compared to conventional speckling methods.

Conclusions

Physical experiments show the scalability of this optimized pattern to allow for varying working distances while consistently maintaining a lower error threshold compared to conventional speckling techniques.

  相似文献   
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New therapeutic options are crucially for most cancers, particularly those with poor clinical outcomes. Five new derivatives of cisplatin-containing selenone ligands with the general formula, cis-[Pt(NH3)2(Selenone)2](NO3)2 (15) were synthesized and characterized using elemental analysis, Infrared, and nuclear magnetic resonance (1H, 13C & 77Se) spectroscopy. Spectroscopic and computational data supported the coordination of selenones to platinum(II). The structures of the complexes were predicted using density functional theory calculations. Molecular docking studies were carried out using the AutoDock Tools docking program. The in vitro cytotoxicity of these complexes and cisplatin against three human cancer cell lines, HeLa, A549, and HCT116 was investigated using the MTT assay. The best candidate complex, complex 3, was subjected to mechanistic assessments, including miRNA profiling, PI3K deactivation, and induction of apoptosis. Docking studies showed that all the newly synthesized platinum(II) complexes interacted with the minor DNA groove. The synthesized complexes showed promising cytotoxic effects against the tested cell lines. Complex 3 modulated the miRNA expression signature in A549 cells. Pathway enrichment analyses of differentially expressed miRNA gene targets identified the PI3K/AKT signaling pathway as a promising target. Complex 3 inhibited PI3K activity and induced apoptosis. Collectively, our study identified promising new platinum(II) derivatives such as complex 3, paving the way for future in vitro and in vivo validations and safety studies.  相似文献   
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Nine compounds including a new cinnamamide (1), N-(1-cinnamoylpyrrolidin-2-yl)cinnamamide, and two compounds (8 and 9) first isolated from natural sources, were obtained from the edible mushroom Pholiota lubrica. Their structures were determined by the interpretation of spectroscopic data. Compounds 1, 3 and 9 exhibited the inhibitory activity against lettuce, while compounds 2 and 7 promoted the growth of lettuce.  相似文献   
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Dehydrogenation or oxidative dehydrogenation (ODH) of alkanes to produce alkenes directly from natural gas/shale gas is gaining in importance. Ti3AlC2, a MAX phase, which hitherto had not been used in catalysis, efficiently catalyzes the ODH of n‐butane to butenes and butadiene, which are important intermediates for the synthesis of polymers and other compounds. The catalyst, which combines both metallic and ceramic properties, is stable for at least 30 h on stream, even at low O2:butane ratios, without suffering from coking. This material has neither lattice oxygens nor noble metals, yet a unique combination of numerous defects and a thin surface Ti1?yAlyO2?y/2 layer that is rich in oxygen vacancies makes it an active catalyst. Given the large number of compositions available, MAX phases may find applications in several heterogeneously catalyzed reactions.  相似文献   
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Polymer blends is a well-established and suitable method to produced new polymeric materials as compared to synthesis of a new polymer. The combination of two different types of polymers will produce a new and unique material, which has the attribute of both polymers. The aim of this work is to analyze mechanical and morphological properties of bio-phenolic/epoxy polymer blends to find the best formulation for future study. Bio-phenolic/epoxy polymer blends were fabricated using the hand lay-up method at different loading of bio-phenolic (5 wt%, 10 wt%, 15 wt%, 20 wt%, and 25 wt%) in the epoxy matrix whereas neat bio-phenolic and epoxy samples were also fabricated for comparison. Results indicated that mechanical properties were improved for bio-phenolic/epoxy polymer blends compared to neat epoxy and phenolic. In addition, there is no sign of phase separation in polymer blends. The highest tensile, flexural, and impact strength was shown by P-20(biophenolic-20 wt% and Epoxy-80 wt%) whereas P-25 (biophenolic-25 wt% and Epoxy-75 wt%) has the highest tensile and flexural modulus. Based on the finding, it is concluded that P-20 shows better overall mechanical properties among the polymer blends. Based on this finding, the bio-phenolic/epoxy blend with 20 wt% will be used for further study on flax-reinforced bio-phenolic/epoxy polymer blends.  相似文献   
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